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This paper is the first in a series of studies generalizing the Map of Expected Earthquakes (MEE) medium-term earthquake forecast method and analyzing the prospects for its further improvement. Over the past 35 years, the MEE method has been used in seismically active regions around the world with different tectonic conditions and seismic regimes. The average prognostic efficiency of the algorithm was shown to be 2.5 times higher than for random guessing. The MEE can be further improved and upgraded. The new methods of data processing to be implemented into the upgraded MEE will significantly increase the amount of analyzed data, take into account the specific signs of the seismic process at different depths, use lineament–domain–focal (LDF) models of the structure of seismically active zones as stationary prognostic criteria, and build three-dimensional distributions of the probability of strong earthquakes. The improvement will involve an expansion of the list of used seismological precursors that have a physically justified link with the earthquake preparation process and the development of formalized techniques for identifying these precursors in the prognostic practice. [ABSTRACT FROM AUTHOR]

We consider some characteristics of seismicity in the region of Southwest Alaska. The aftershock zones of the Simeonof (July 22, 2020, Mw = 7.8) and Chignik (July 29, 2021, Mw = 8.2) earthquakes are identified. The characteristics of ring-shaped seismicity structures, which formed in a few decades prior to the Chignik earthquake, are described. The location and magnitude of a large event, which could be prepared to the east of the Simeonof earthquake rupture zone, was predicted in (Kopnichev and Sokolova, 2021a) based on the parameters of these structures. An estimate of the expected magnitude (Mw = 8.2 ± 0.2) was obtained using correlation dependences between the parameters of ring-shaped structures and the magnitudes of large and great earthquakes that occurred in the East Pacific region. This forecast, which was made on the basis of the data obtained prior to October 21, 2020, was presented in the mentioned paper, which was accepted for publication before July 29, 2021. We consider possible changes of the parameters of ring-shaped structures immediately prior to the Chignik earthquake and discuss geodynamic processes that can lead to the formation of ring-shaped structures. [ABSTRACT FROM AUTHOR]